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Shock. Dr. Mohammad Al-Adaileh M.B.B.S, MRCSI Fellow of Thoracic surgery Department of Surgery Faculty of Medicine Jordan University Hospital University of Jordan. Extra information were added to the slide. Objectives. Definition Approach to the hypotensive patient Types
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Shock Dr. Mohammad Al-Adaileh M.B.B.S, MRCSI Fellow of Thoracic surgery Department of Surgery Faculty of Medicine Jordan University Hospital University of Jordan Extra information were added to the slide
Objectives • Definition • Approach to the hypotensive patient • Types • Specific treatments
Definition of Shock • Inadequate oxygen delivery to meet metabolic demands • Results in global tissue hypoperfusion and metabolic acidosis • Shock can occur with a normal blood pressure and hypotension can occur without shock
Types of Shock • Cardiogenic: causes: Ischemic heart disease, vasoconstruction • Hypovolemic: The most common one • Distributive shock: Vasodilatation in periphery (limbs), (decrease resistance) and vasoconstruction in an important areas (increase resistance in the central parts) • Septic: • Anaphylactic • Neurogenical: Loss of sympathetic response • Obstructive: Ex. Neumothorex: air in plural cavity that compress the major vesseles
68 yo M with hx of HTN and DM presents to the ER with abrupt onset of diffuse abdominal pain with radiation to his low back. The pt is hypotensive, tachycardic, afebrile, with cool but dry skin Types of Shock Hypovolemic Septic Cardiogenic Anaphylactic Neurogenic Obstructive What Type of Shock is This? Hypovolemic Shock
Hypovolemic Shock • Non-hemorrhagic • Vomiting • Diarrhea • Bowel obstruction, pancreatitis (due to effect of what so called third spacing which mean moving of fluid from intravascular third spacing) • Burns (also third spacing) • Neglect, environmental (dehydration) • Hemorrhagic • GI bleed • Trauma • Massive hemoptysis • AAA rupture (Abdominal Aortic Aneurysm rapture), any abdominal pain radiating to the lower back especially in elderly pts) • Ectopic pregnancy, post-partum bleeding
Notes: • Crystalloid: Normal saline and Ringer's lactate • Pulse pressure = systolic - diastolic
Hypovolemic Shock • ABCs • Establish 2 large bore IVs or a central line • Crystalloids • Normal Saline or Lactate Ringers (give 20ml/kg) Exam question • Up to 3 liters • PRBCs (Colloids) • O negative or cross matched (except female in child bearing age, we give her O- ) • Control any bleeding • Arrange definitive treatment
Cardiogenic Shock • Pump Failure • Causes: acute MI CHF obstruction arrhythmias
Treatment of Cardiogenic Shock • Goals- (1)Airway stability and improving myocardial pump functionthough two large pore cannulas fluid supply & we give Dobutamine to increase the contractility • Cardiac monitor, pulse oximetry • Supplemental oxygen, IV access • Intubation will decrease preload and result in hypotension • Be prepared to give fluidbolus
Treatment of Cardiogenic Shock • AMIمش مهم • Aspirin, beta blocker, morphine, heparin • If no pulmonary edema, IV fluid challenge • If pulmonary edema • Dopamine – will ↑ HR and thus cardiac work • Dobutamine – May drop blood pressure • Combination therapy may be more effective • PCI or thrombolytics • RV infarct • Fluids and Dobutamine (no NTG) • Acute mitral regurgitation or VSD • Pressors (Dobutamine and Nitroprusside)
Obstructive Shock • Causes • Cardiac Tamponade • Tension Pneumothorax • Massive Pulmonary Embolus • Signs • cardiac output • PAOP • SVR”Systemic Vascular Resistance-cold dry skin like in Hypovolemic Shock and Cardiogenic Shock
Anaphylactic Shock • Anaphylaxis – a severe systemic hypersensitivity reaction characterized by multisystem involvement • IgE mediated • Anaphylactoid reaction – clinically indistinguishable from anaphylaxis, do not require a sensitizing exposure • Not IgE mediated
Anaphylactic Shock • What are some symptoms of anaphylaxis? • First- Pruritus, flushing, urticaria appear • Next- Throat fullness, anxiety, chest tightness, shortness of breath and lightheadedness • Finally- Altered mental status, respiratory distress and circulatory collapse
Anaphylactic Shock • Risk factors for fatal anaphylaxis • Poorly controlled asthma • Previous anaphylaxis • Reoccurrence ratesمش مهمه • 40-60% for insect stings • 20-40% for radiocontrast agents • 10-20% for penicillin • Most common causes • Antibiotics # 1 • Insects • Food
Anaphylactic Shock • Mild, localized urticaria can progress to full anaphylaxis • Symptoms usually begin within 60 minutes of exposure • Faster the onset of symptoms = more severe reaction • Biphasic phenomenon occurs in up to 20% of patients • Symptoms return 3-4 hours after initial reaction has cleared • A “lump in my throat” and “hoarseness” heralds life-threatening laryngeal edema
Anaphylactic Shock- Diagnosisمش مهمة • Clinical diagnosis • Defined by airway compromise, hypotension, or involvement of cutaneous, respiratory, or GI systems • Look for exposure to drug, food, or insect • Labs have no role
Anaphylactic Shock- Treatment • ABC’s • Angioedema and respiratory compromise require immediate intubation • IV, cardiac monitor, pulse oximetry • IVFs, oxygen • Epinephrine • Second line • Corticosteriods • H1 and H2 blockers
Anaphylactic Shock- Treatment • Epinephrine • 0.3 mg IM of 1:1000 (epi-pen) • Repeat every 5-10 min as needed • Caution with patients taking beta blockers- can cause severe hypertension due to unopposed alpha stimulation • For CV collapse, 1 mg IV of 1:10,000 • If refractory, start IV drip
Anaphylactic Shock - Treatment • Corticosteroids • Methylprednisolone 125 mg IV • Prednisone 60 mg PO • Antihistamines • H1 blocker- Diphenhydramine 25-50 mg IV • H2 blocker- Ranitidine 50 mg IV • Bronchodilators • Albuterol nebulizer • Atrovent nebulizer • Magnesium sulfate 2 g IV over 20 minutes • Glucagon • For patients taking beta blockers and with refractory hypotension • 1 mg IV q5 minutes until hypotension resolves
Anaphylactic Shock - Disposition • All patients who receive epinephrine should be observed for 4-6 hours • If symptom free, discharge home • If on beta blockers or h/o severe reaction in past, consider admission
A 41 yo M presents to the ER after an MVC complaining of decreased sensation below his waist and is now hypotensive, bradycardic, with warm extremities“في البدايه فقط“ Types of Shock Hypovolemic Septic Cardiogenic Anaphylactic Neurogenic Obstructive What Type of Shock is This?مهم Neurogenic
Neurogenic Shock • Occurs after acute spinal cord injury • Sympathetic outflow is disrupted leaving unopposed vagal tone • Results in hypotension and bradycardia • Spinal shock- temporary loss of spinal reflex activity below a total or near total spinal cord injury (not the same as neurogenic shock, the terms are not interchangeable)
Neurogenic Shock • Loss of sympathetic tone results in warm and dry skin • Shock usually lasts from 1 to 3 weeks • Any injury above T1 can disrupt the entire sympathetic system • Higher injuries = worse paralysis
Neurogenic Shock- Treatment • A,B,Cs • Remember c-spine precautions • Fluid resuscitation • Keep MAP at 85-90 mm Hg for first 7 days • Thought to minimize secondary cord injury • If crystalloid is insufficient use vasopressors • Search for other causes of hypotension • For bradycardia • Atropine • Pacemaker
Neurogenic Shock- Treatment • Methylprednisolone • Used only for blunt spinal cord injury • High dose therapy for 23 hours • Must be started within 8 hours • Controversial- Risk for infection, GI bleed
A 24 yo M presents to the ED after an MVC c/o chest pain and difficulty breathing. On PE, you note the pt to be tachycardic, hypotensive, hypoxic, and with decreased breath sounds on left Types of Shock Hypovolemic Septic Cardiogenic Anaphylactic Neurogenic Obstructive What Type of Shock is This? Obstructive
Obstructive Shock • Tension pneumothorax • Air trapped in pleural space with 1 way valve, air/pressure builds up • Mediastinum shifted impeding venous return • Chest pain, SOB, decreased breath sounds • No tests needed! • Rx: Needle decompression, chest tube
Obstructive Shock • Cardiac tamponade • Blood in pericardial sac prevents venous return to and contraction of heart • Related to trauma, pericarditis, MI • Beck’s triad: hypotension, muffled heart sounds, JVD“Jugular vein distention“ • Diagnosis: large heart CXR, echo • Rx: Pericardiocentisis
Obstructive Shock • Pulmonary embolism • Virscow triad: hypercoaguable, venous injury, venostasis • Signs: Tachypnea, tachycardia, hypoxia • Low risk: D-dimer • Higher risk: CT chest or VQ scan • Rx: Heparin, consider thrombolytics
Septic Shock Definitions in Sepsis • Systemic inflammatory response syndrome (SRIS); two of: • Hyperthermia (> 38 0 C). • Tachycardia (> 90/ min no β-blockers) or tachypnea (20/min. • White cell count > 12X109/liter or < 12X109/liter) • Sepsis is SIRS with a documented infection • Severe sepsis or septic syndrome is sepsis with evidence of one or more organ failure (respiratory (ARDS), cardiovascular, renal (ATN) or CNS). • If hypotention occure either with sepsis or severe sepsis we call it septic shock
The End Any Questions?